Answer :
Final answer:
In prokaryotes, the regulation of biosynthetic metabolic pathways often involves regulatory molecules such as repressors, activators, and inducers, which can inhibit or stimulate gene transcription. Specific examples include repressible operons like the trp operon and mechanisms like riboswitches.
Explanation:
For biosynthetic metabolic pathways in prokaryotes, the regulatory molecule is often repressors, activators, and inducers. These molecules play key roles in affecting the expression of operons. For instance, repressors, as the name implies, suppress the transcription of a gene in response to an external stimulus. Activators, on the other hand, increase the transcription of a gene in reaction to an external stimulus. Lastly, inducers are small molecules that either activate or repress the transcription process, depending on the substrate availability and the cell's needs.
On a more specific level, biosynthetic pathways involve repressible operons, like the tryptophan (trp) operon, which contain genes encoding enzymes for a biosynthetic pathway. As long as the cell requires the product of the pathway, the repressible operon continues to be expressed. However, once the pathway's product accumulates in the cell, expression is repressed, indicating that the cell no longer needs to continue synthesis.
Another example is the use of a riboswitch, a small region of noncoding RNA found within the 5' end of some prokaryotic mRNA molecules. This riboswitch can bind to a small intracellular molecule, stabilizing certain secondary structures of the mRNA molecule, thus influencing the completion of mRNA synthesis and protein synthesis.
Learn more about Biosynthetic Metabolic Pathways here:
https://brainly.com/question/34452144
#SPJ11
